Sound reproducing system



Nov. 12, 1968 W, R, BEHNKE ET AL 3,410,947

SOUND REPRODUCING SYSTEM Filed June 24, 1965 3 Sheetsf-Sheet l zwum@2:30a

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INVENTORS WALLACE R. BEHNKE cURT R.R.woLFANGER /i w d /E-k..

ATTORNEYS Nov. 12, 1968 Filed June 24, 1965 FIGB W. R. BEHNKE ET AL3,410,947

SOUND REPRODUCING SYSTEM 5 Sheets-Sheet 2 mvENToRs WALLACE R. BEHNKEcURT RR. woLFANGER l l/v... a, ud-wf ATTORNEYS Nov. 12, 1968 n FiledJune 24, 1965 W. R. BEHNKE ET AL 3 Sheets-Sheet 3 5B 5o 27 39 lo FIG 555 54 52 PIPE SPEAKER f o AMP. o-

i l[ l 57 r f ELECTRONIC 53 69j 29 [66 oRGAN o( SIGNAL o TREMoLo o 65GENEQAJOR 7 oScaLLAToR RoToR l SPEAKER 1l- 58 56 L68 e? 6| v W Y,

e2 BASS y P AKER 64 S3 S E l( oSclLLATlNG MECHANISM OSCILLATINGMECHANISM INVENTORS WALLACE R. BEHNKE CURT R. R. WOLFANGER United StatesPatent O 3,410,947 SOUND REPRODUCING SYSTEM Wallace R. Behnke and CurtR. R. Wolfanger, Elkhart, Ind., assignors to C. G. Conn Ltd., Elkhart,Ind., a corporation of Indiana Filed June 24, 1965, Ser. No. 466,668 12Claims. (Cl. 84-1.01)

ABSTRACT F THE DISCLOSURE Sound reproducing system for electric organhaving a multiplicity of pipes of different lengths and diametersprojecting from a Wall, with loud speakers producing sound on theopposite side of the wall. A baffle of substantial thickness has slotstherein for coupling each speaker to a plurality of pipes. Tremolo andother effects can be provided by modulating the signal applied to thespeakers and/or by movable mechanical Ameans in the path of the soundwaves. The pipe speaker assembly may be utilized with a bass speakerand/or a rotor speaker.

This invention relates to a sound reproducing system and moreparticularly to such a system for an electronic organ and which includesone or more sound reproducers and resonant pipes operative to generatetones and sound effects similar to those produced by a pipe organ.

Arrangements have heretofore been proposed using pipes in conjunctionwith conventional speakers to enhance tonal qualities, but sucharrangements have/been of quite limited value particularly with respectto efficiency of reproduction, with respect to the number of pipes whichcan be used, and with respect to the attainment of a satisfactorybalance in the production of tones of various frequencies.

The present invention was evolved with the general object of overcomingsuch disadvantages of prior systems and with the specific object ofproviding a sound reproducer for an electronic organ system using pipesto produce tones and sound effects similar to those produced by a pipeorgan,while avoiding the high cost, large size;` and other disadvantagesof the pipe organ.

According to an important feature of this invention, electrical signalsof selected frequencies and harmonic contents, such as produced by knownelectronic organ circuitry, are applied to a plurality of speakers, eachof which is efficiently coupled directly to the ends of a limited numberof pipes, with the pipes beipg of various lengths such as to resonate atfrequencies corresponding to the fundamental and/or harmonic frequencycomponents of the applied signals. With this'arrangement, it is possibleto utilize pipes in numbers sufficient to obtain an extended tonal rangebut with a balanced excitation such as to produce .an effect similar tothat produced by the pipe organ. Due to the resonance of theA pipes, thebuild-up of sound is grad-ual and likewise the decay is gradual, with asoftened attack and release effect like that obtained with the pipeorgan, but not obtained with conventional speakers, An effectivedispersion of sound is produced without the directional effects ofconventional speakers. At the sarne time, the pipes do not requiretuning, since the sound is produced by thespeakers.` Further, thereproducer is relatively simple and inexpensive in construction vanddoes not require the blower and other equipment of the conventional pipeorgan.

An important feature of the invention relates to a coupling arrangementfor obtaining an efficient and balanced excitation of a plurality ofpipes directly from a speaker. In accordance with this feature, thespeaker is mounted on the inside with respect to a wall having openingsinto which the inner ends of a plurality of pipes are secured,

3 ,4 0,94 7 Patented Nov. l2, 1968 ICC and means are provided projectinginwardly from the wall toward the speaker to reduce the volume and todefine close coupling means which efficiently channels and distributesthe sound waves from the speaker into the ends of the pipes. V

In accordance with a specific feature of the invention, the coupling isprovided by a baffle of substantial thickness on the inner surface ofthe wall, the baille having a plurality of slots therein each alignedwith openings disposed in a row, with the sound being channelled anddistributed from the spea-ker through the slots into the ends of thepipes.

According to another important feature of the invention, the pipe endsare secured in openings extending along one Iwall of an elongatedenclosure, with the speakers being mounted within the enclosure inspaced relation therealong. With this arrangement, a compact soundreproducer is provided which can be readily disposed against a wall, oron top of a console.

According to a specific feature of the invention, elliptical speakersare used with `an arrangement of pipes such as to obtain close couplingand high efficiency, with each speaker being effective to supply soundwaves into several pipes.

A further important feature of the invention relates to the modulationat a sub-audible rate of the amplitude of sound developed in the pipes,to produce a tremolo, chortle effect, or the like. This feature isimportant in that the same slow build-up and decay of the sound isproduced as with a conventional pipe organ while using energization byelectrical signals. The same effect is not obtainable with theconventional speaker systems of electronic organs. In a preferredembodiment ofy the invention, the modulation means comprises electronicmeans for modulating the amplitude of electrical signals applied fromamplier means to the speakers. In other embodiments, the modulationmeans comprises mechanical Imeans in the path of sound waves transmittedfrom the speaker through the pipes for Varying the transmission v-of thewaves.

Still another feature of the invention relates to piercing of pipes toopen the sound, produce natural wind and to induce other harmonics. Amore specific feature relates to the use of piercing to enable a pipehaving a closed end to emit sound and to produce the desired effects.With this arrangement tones an octave lower can be produced with a pipeof the same length.

This invention contemplates other and more specific objects, featuresand advantages which will become more fully apparent 'from the followingdetailed description taken in conjunction With the accompanying drawingswhich ill-ustrate preferred embodiments and in which:

FIGURE 1 is a perspective view of a sound reproducer in the form of apipe speaker constructed according to the principles of this invention;

FIGURE 2 is a top plan view of the pipe speaker of FIGURE'l;

FIGURE 3 is a vertical sectional view taken substantially along the lineIII- III of FIGURE 2;

FIGURE 4 is a horizontal sectional view taken substantially along theline IV-IV of FIGURE 3;

FIGURE 5 is a circuit diagram of an electronic organ system using thepipe speaker of FIGURES 1 4;

FIGURE 6 is a diagrammatic View of a modification of the speaker ofFIGURE l using an oscillating plate for controlling supply of sound intothe ends of the pipes;

FIGURE 7 is a diagrammatic View of another modification similar to thatof FIGURE 6 but using a rotating baffle;

FIGURE 8 is a diagrammatic View of still another modification using anoscillating plate at the upper ends of Pipes;

FIGURE 9 illustrates a portion of a speaker similar to FIGURE 1, butwith a modified construction having holes in the pipes; and

FIGURE 10 is a view similar to FIGURE 9, but illustrating a modificationusing holes in connection with closed pipes.

Referring to FIGURES 1 to 4, reference numeral 10 generally designates asound reproducer constructed according to the principles of thisinvention, designed for use in an electronic organ system. Thereproducer 10 comprises an elongated generally rectangular enclosure 11having a top wall 12, a bottom wall 13, a front wall 14, a back wall 15and end walls 16 and 17. Preferably, the walls are of wood withdove-tailed and glued joints.

In accordance with this invention, the top wall 12 is formed with twogenerally parallel rows of openings therein, a front row of openings 19and a rear row of openings 20, into which are tightly fitted the lowerends of a multiplicity of vertical pipes of various lengths arranged ina front row of pipes 21 and a rear row of pipes 22. The d openings 19and 20 are preferably provided with reduced diameter lower end portionsdefining annular shoulders for receiving the lower ends of the pipes 21and 22 thereagainst (FIG. 3), to prevent the pipes from being pusheddownwardly into the enclosure 11.

Various arrangements of the pipes are possible. In the illustratedreproducer, there are twenty-eight of the pipes 21 in the front rowarranged with the longer pipes on the outside, decreasing in lengthtoward the center, while there are twenty-one of the pipes 22 in theback row with shorter pipes on the outside increasing in length towardthe center, the pipes in the center of the back row being longer thanthose on the ends of the front row. Thus the arrangement is generallysymmetrical, but it is not exactly symmetrical because no two pipes havethe same lengths. Instead, their lengths are ystepped to be resonant atdifferent frequencies of an extended range, corresponding to notes inthe middle and upper frequency range of an electronic organ. The pipesare also not of uniform diameters, the shorter pipes having smallerdiameters.

By way of example and not by way of limitation, the overall length ofthe illustrated enclosure 11 may be fortyone and five-eighths inches andthe dimensions of the pipes and other components may be proportioned asillustrated.

To provide additional support for the longer pipes, a plate 23 isprovided which is supported by spacer sleeves 24 in spaced relationabove the top wall 12, having openings for all of the pipes 22 of therear row and having openings for pipes at the opposite ends of the frontrow, the plate having a cut-out portion 25 so as not to receive theshorter pipes at the center of the front row, which do not require theadditional support.

In the illustrated embodiment, four oval or elliptical speakers 27, 28,29 and 30 are provided in the enclosure 11 in spaced relationtherealong, each arranged to project sound into the lower ends of aplurality of pipes. Thus the left-hand speaker 27 is positioned toproject sound into the ends of the first five pipes of the front row andthe first five pipes of the rear row (starting from the left as viewedin the drawings); the second speaker 28 is positioned to project soundinto the next nine pipes of the front row and the next five pipes of therear row; the third speaker 29 is arranged to project sound into thenext eight pipes of the front row and the next five pipes of the rearrow; and the fourth speaker 30 is arranged to project sound into thelast six pipes of the front row and the last six pipes of the rear row.

With`this arrangement, a relatively large number of pipes can be usedwith a relatively small number of speakers and yet a balancedperformance is obtained over the v entire frequency range. The elongatedform of the enclosure and the use of oval speakers are important in thatthe pipes are in side-by-side relation with none of the pipes beingsurrounded by other pipes, thereby to mini- All).

mize interference effects. At the same time, the unit can be readilyplaced on top of an organ console or against a wall. A further advantageis in appearance, with the generally symmetrical arrangement of pipesbeing that associated with a conventional pipe organ.

According to an important feature of the invention, means are providedfor increasing the closeness of coupling between the speakers and thepipes to produce maximum efiiciency and to allow a maximum number ofpipes to be used with a given tone area, while obtaining balancedexcitation of the pipes. In accordance with this feature, a bafflemember 32 (FIG. 4), preferably of wood, is interposed between the topwall 12 and the speakers 27-30 and is provided with a pair of slots foreach speaker. These slots are aligned with the front and rear rows oftop wall openings and expose the pipes to the corresponding speakers. Inparticular, slots 33 and 34 are provided above the speaker 27respectively aligned with the first five front row openings 19 and thefirst five rear row openings 20. Similarly, front and rear slots 35 and36 are provided above speakers 28, front and rear slots 37 and 38 areprovided above the speaker 29 and front and rear slots 39 and 40 areprovided above the speaker 30.

With this arrangement, a chamber of small volume is provided above thespeaker cone, and the acoustical compliance is very small, while theslots serve as coupling sections to smoothly direct the sound waves intothe ends of the pipes. As a result very tight acoustical coupling isobtained to produce high efficiency while also obtaining a balancedexcitation of the pipes. The use of the slots is'particularlyadvantageous in that it facilitates use of the elongated enclosure andmultiple oval speaker features, with the pipes arranged in continuousrows.

According to a specific feature of the invention partition members 41,42 and 43 are provided to cooperate with the end Walls 16 and 17 indefining four separate back chambers for the speakers 27-30, thusminimizing the possibility of interference effects.

FIGURE 5 is a circuit diagram of a system for energizing the speakers27-30. In this system, a circuit point is connected through speakers 27and 28 in series to ground and through speakers 29 and 30 in series toground. Circuit point 50 is connected to the output of an amplifier 51.having an input normally connected through a selector switch 52 to thejunction between resistors 53 and 54. Resistor53 being connected toground and resistor 54 beinglconnected through a capacitor 55 to aselector switch 56, for selective connection to output terminals 57 and58 ofan electronic organ signal generator 60. A speaker 61 ofy-a bassspeaker enclosure 62 is connected through a filter including capacitor63 and resistor 64 to the selector switch 56.

Resistors 53 and 54 and capacitor 55 form a high pass filter forapplying frequency components above a crossover frequency to the pipespeakers 27-30 while capacitor 63 and resistor 64 form a low pass filterfor applying frequency components below the crossover frequency to thebass speaker 61. With this arrangement, the pipe speaker can producefrequency components in the middle and upper frequency range, and thelower frequency components are produced by the bass speaker enclosure.This is highly desirable in that the lowest frequency to be reproducedby the pipe speaker can be relatively high, thus reducing the requiredlength of the longest pipe, and the required number of pipes so that theunit can be of relatively small size. At the same time, excellentquality of sound is obtained, approaching that of a pipe organ, evenwith the lower frequency tones. An important contributing factor is thefact that the pipes of the pipe speaker resonate at harmonics of thelower frequency tones, and a pronounced pipe organ effect is obtainedwith such tones.

The overall efficiency of the reproducer 10 is substantially less thanthat of a conventional reproducer, because consider-able energy isconsumed in dispersing the sound through the pipes. Accordingly, theamplifier 51 is normally required, as when the system is used forproducing diapason tones. In other circumstances, however, the amplifier51 may not be required, particularly in producing flute tones, which aremore sinusoidal in nature than the complex voices, and the pipes do notrequire much power to be effective. Thus, with switch 56 connected tothe terminal 58, which may be assumed to be the output of the flutechannel, the switch 52 may be operated to connect to the output of thehigh pass filter directly to the pipe speaker 10.

The speaker system may also incorporate a rotor speaker in an enclosure66, which may be connected through a selector switch 67 to the circuitpoint 50. The combination of the rotor speaker with the pipe speaker ishighly effective in that although the rotor speaker generally produces`good ethereal and celeste effects, the constant moving of the rotorrobs the fiute tone of its presence and can cause the organistdifficulty in playing fast passages on the high flute pitches. The pipespeaker does not destroy the moving, life-like quality that the lowrotor produces, but adds the life and pipe-like quality to the top ofthe fiute tones.

As above discussed, the pipes, being resonant, cause a slow build-up anda slow decay of tones which is highly desirable in achieving the sameeffect as obtained with a pipe organ. It is found that this effect isalso highly advantageous in tremolo or chortle effects, or the like. Inthe illustrated system, the tremolo effect is obtained in a very simplemanner electronically, by connecting a tremolo oscillator 68 to theamplifier 51, through switch 69. Thus, by merely modulating the outputof the amplifier 51 at a low frequency, the tremolo effect is readilyobtained, and it is enhanced by the slow build-up and decaycharacteristics which are obtained with the resonant pipes.

FIGURE 6 diagrammatically illustrates a modified arrangement formechanically producing the tremolo or chortle effect. In thisarrangement, a plate 70 having a form similar to that of the baffleplate 32 and having slots therein aligned with the slots of the bafiieplate, including slots 71 and 72 corresponding to slots 39 and 40 of thebaffle plate 32, is interposed between the baffle plate 32 and the topwall 12 of the enclosure. The plate 70 is oscillated at a low frequencyby an oscillating mechanism 73, in af direction transverse to thedirection of the slots.

FIGURE 7 diagrammatically illustrates another modified arrangement formechanically producing tremolo or chortle effects, wherein a plate 74 isprovided for substitutionfor the bae plate 32, the plate 74 having apair of slots 75 and 76 for extending under the pipe ends, with rotors77 and 78 being provided in these slots 75 and 76, and being rotated bya suitable rotating mechanism 79.

FIGURE 8 illustrates still another modified arrangement for producingtremolo or chortle effects, wherein pipes 80 are installed on anenclosure 81, having speakers therein and constructed in the same manneras the enclosure 11, but with the pipes 80 being arranged so that thedownwardly inclined plate 82 is aligned in co-planer relation with theupper ends of the pipes. As diagrammatically illustrated, a plate 83having openings 84 corresponding to the openings in the ends of thepipes may be disposed against the plate 82, and may be oscillated by anoscillating mechanism 85 to produce the desired effect.

FIGURE 9 illustrates a modified arrangement wherein a front row of pipes87 and a rear row of pipes 88 are substituted for the front row of pipes21 and the rear row of pipes 22 of the reproducer 10 of FIGURES 1 and 4.The pipes may be identical to those of the reproducer 10, except theyhave holes 89 and 90 therein positioned approximately midway between thelower and upper ends thereof. The openings preferably have a size on theorder of from 1434 to 1A of an inch. Such openings produce increasedharmonics, predominately odd harmonics since a clarinet-like tone isadded to the fundamental resonance.

The openings also produce rushing wind and whistle blowing sounds.

FIGURE 10 illustrates an arrangement which is the same as that of FIGURE9, except that caps 91 and 92 are placed on the upper ends of the frontand rear rows of pipes 87 and 88, to provide stopped or closed pipes.The closed pipes resonate at a frequency lower than that obtained withthe open pipes. Thus a lower range -of frequency of operation may beobtained, or in the alternative, the pipes may be made shorter to obtainthe same range of frequency. The provision of the openings 89 isnecessary to allow emanation of sound from the pipes, and at the sametime, the openings produce additional harmonics, as may be desired.

It will be understood that modifications and variations may be effectedwithout departing from the spirit and scope of the novel concepts ofthis invention.

We claim:

1. A sound reproducer including in combination, a wall having aplurality of openings therein arranged in a row, a plurality of pipeseach having an end secured in one of said openings to project outwardlyfrom said wall, a baffle of substantial thickness on the inner surfaceof said wall having a plurality of slots therein aligned with theopenings in said row, and a plurality of speakers on the inward side ofsaid baffle and each projecting sound through one of said slots into theends of a plurality of said pipes, each of said slots defining couplingmeans effective to channel and distribute sound from one of saidspeakers into the ends of a plurality of said pipes.

2. In a sound reproducer for use with an electronic organ, a wall havingopenings therein arranged in a row, a plurality of pipes of varyinglengths each having an end disposed in one of said openings to projectoutwardly from said wall, a baffle of substantial thickness on the innerside of said wall having a slot therein aligned with the openings insaid row, and an oval speaker behind said wall having its longerdimension aligned with the row of openings for projecting sound throughsaid slot and through all of said openings into the ends of said pipes,

said slot defining coupling means effective to channel and distributesound from said speaker into the ends of said pipes.

3. In a sound reproducer for use with an electronic organ, a wall havingopenings therein arranged in substantially parallel rows with aplurality of openings in each row, a plurality of pipes each having anend secured in one of said openings to project outwardly from said wall,a baffle of substantial thickness on the inner surface of said wallhaving a plurality of substantially parallel elongated slots thereineach aligned with the openings in one of said rows, and a speaker on theinward side of said baffle for projecting sound through said slots andthe ends of said pipes, said slots defining coupling means effective tochannel and distribute sound from said speaker into the ends of saidpipes.

4. A sound reproducer including in combination, a wall having openingstherein arranged in two rows with at least three openings in each rowand with the spacing between rows and the spacings between openings ofeach row being approximately equal, a plurality of pipes of varyinglengths each having an end disposed in one of said openings to projectoutwardly therefrom, a bafiie of substantial thickness on the inner sideof said wall having a plurality of slots therein each aligned with theopenings in one of said rows, and a plurality of oval speakers on theinward side of said baie having the longer dimensions thereof alignedwith said slots for projecting sound therethrough and through all ofsaid openings into the ends of said pipes, each of said slots definingcoupling means effective to channel and distribute sound from one ofsaid speakers into a plurality of said pipes.

5. In a sound reproducer for use with an electronic organ, an elongatedenclosure having a multiplicity of openings arranged in rows along onewall thereof, a multiplicity of pipes of varying lengths and diametershaving inner ends secured in said openings to project in parallelrelation from `said wall, a plurality of speakers mounted within saidenclosure in spaced relation therealong each arranged to project soundthrough a plurality of said openings in at least two rows and into saidpipes secured therein, and a plurality of partitions within saidenclosure in spaced relation therealong and disposed between saidspeakers to deline a separate chamber for each of said speakers.

6. A sound reproducer including in combination, wall means having amultiplicity of openings therein, a multiplicity of pipes of varyinglengths each having an inner end secured in one of said openings toproject outwardly from said wall means, a plurality of speakers on theinward side of said wall means, baille means between said wall means andsaid speakers and having slots therein coupling sound from said speakersto said inner ends of said pipes, and means completely closing the outerends of at least a plurality of said pipes, said last-mentionedplurality of pipes having openings therein intermediate the inner andouter ends thereof for emanation of sound from said pipes.

7. A sound reproducing system for reproducing signals at selectedfrequencies, including in combination, a bass speaker unit, a pipespeaker unit, low pass and high pass filter means for respectivelyapplying signals to be reproduced respectively to said bass speaker unitand said pipe speaker unit, said pipe speaker unit comprising wall meanshaving a multiplicity of openings therein, a multiplicity of pipes eachhaving an inner end secured in one of said openings to project outwardlyfrom said wall means, and speaker means mounted inwardly from said `wallmeans and arranged to project sound into said inner ends of a pluralityof said pipes.

8. A system as defined in claim 7 including a booster amplifier forapplying signals to said pipe speaker unit.

9. A sound reproducing system for an electronic organ including incombination, a pipe speaker unit, a rotor speaker unit, means forapplying signals to both said speaker units, said pipe speaker unitcomprising wall means having a multiplicity of openings therein, amultiplicity of pipes each having an inner end secured in one of saidopenings to project outwardly from said wall means, and a plurality ofspeakers mounted inwardly from said wall means and each arranged toproject sound into the inner end-s of a plurality of said pipes.

10. In a sound reproducer for an electronic organ, wall means having amultiplicity of openings therein, a multiplicity of pipes of varyinglengths each having-an inner end secured in one of said openings toproject outwardly from said wall means, speaker means'arranged toproject sound into said inner ends of said pipes, and oscillatingmechanical means adjacent to the outer ends of said pipes and having aportion extending in the path of sound therefrom for mechanicallymodulating the sound output therefrom.

11. A sound reproducer including in combination, wall means having amultiplicity of openings therein, a multiplicity of pipes of varyinglengths each having an inner end secured in one of said openings toproject outwardly from said wall means, speaker means arranged toproject sound into said inner ends of said pipes, and oscillatingmechanical means interposed between said speaker means and the innerends of said pipes and having a portion extending in the path of thesound for mechanically modulating the sound applied to said pipes.

12. A sound reproducer including in combination, a wall having aplurality of openings therein arranged in a row, a plurality of pipeseach having an end secured in one of said openings to project outwardlyfrom said wall, a baille of substantial thickness on the inner surfaceof said wall having a slot therein aligned with the openings in said rowfor applying sound to said ends of said pipes, and an additional bailleadjacent to the rstmentioned baille and having a slot aligned with theslot therein, said additional baille being movable in a directiontransverse to said slot to modulate the soundapplied to said ends ofsaid pipes.

References Cited UNITED STATES PATENTS 965,897 8/1910 Haskell 84--3492,150,210 3/1939 Dreyfus 181--31 2,619,866 12/1952 Bailey 84-3492,780,302 2/1957 George 18127 2,952,179 9/1'960 Andersen 84-1.243,267,196 8/1966 Welsh et al. 84-1.24

FOREIGN PATENTS 1,073,838 l/l960 Germany.

ARTHUR GAUSS, Primary Examiner.

B. P. DAVIS, Assistant Examiner.

